Field of the Invention
The invention relates generally to communication networks. More specifically, the invention relates to maintenance of high availability in an enterprise IMS network.
Description of Related Art
Generally, applications that are deployed at the applications layer of an IMS network frequently carry out business critical functions. Therefore, high availability and zero service interruption are important considerations for such applications. Conventionally, many enterprise IMS applications implement the high availability by the server in the active role sending information using an out-of-band mechanism to its nominated standby server. Often, specialist application vendors are forced into this complex approach as they have no influence or product capability in the area of IMS session management.
Another method of achieving the goal of maintaining high availability and zero service interruption may be through redundancies, i.e. by having multiple backup servers that are capable of taking over, in the event of complete failure of the one or more servers. The difficulty in implementing that goal is that the redundant component(s) cannot be normally and naturally used as a standby server while still being included in the signaling path, i.e. the redundant components do not normally and naturally receive the same information that the primary component receives. Additionally, maintenance of the redundant components is very expensive and difficult.
Therefore, improvements in the conventional technology, of providing high availability of application servers, are required to implement the highly available servers in an easier and cheaper manner. Further, techniques are required to improve the reliability on the fault tolerance capabilities of the application servers to ensure zero downtime in the events of failure.